Safety and effectiveness of controlled-release paroxetine in routine clinical practice: results of a postmarketing surveillance study of patients with depression

Abstract

ObjectiveSelective serotonin reuptake inhibitors are commonly used in the pharmacotherapy of depression. However, adverse events can lead to their early discontinuation. This study evaluated the safety and effectiveness of paroxetine controlled-release (CR) tablets in Japanese patients with depression/depressive state (hereafter referred to as depression) in routine clinical practice in Japan.Patients and methodsThis was an open-label, noninterventional, prospective, postmarketing surveillance study. A total of 3,213 patients aged 12–92 years with depression were prescribed paroxetine CR for 8 weeks at the physician’s discretion. Safety was evaluated on the basis of the reporting of adverse drug reactions. Effectiveness was evaluated on the basis of the physician’s assessment using the Clinical Global Impression-Global Improvement (CGI-GI) and the Clinical Global Impression-Severity of Illness (CGI-SI) scales, as well as on the basis of the patients’ self-reported satisfaction. The primary effectiveness outcome was the improvement rate based on the physician’s assessment using the CGI-GI.ResultsThe incidence of adverse drug reactions was 11.2% (359/3,213; 95% confidence interval [CI]: 10.1%–12.3%). The common adverse drug reactions that accounted for 1.0% or more of the incidence were nausea (3.5%) and somnolence (2.7%). The proportion of patients who continued paroxetine CR at week 8 was 80.2% (2,577/3,213; 95% CI: 78.8%–81.6%). The improvement rate at week 8 (last observation carried forward) was 72.8% (2,132/2,927; 95% CI: 71.2%–74.4%). The proportion of patients with CGI-SI scores of moderately or severely ill decreased from 63.6% at baseline to 17.9% at week 8. The proportion of patients who were satisfied with paroxetine CR treatment was 69.8% (2,040/2,921; 95% CI: 68.1%–71.5%).ConclusionThe results of this study suggest that paroxetine CR is a well-tolerated and efficacious treatment for depression in routine clinical practice.

Comparative effectiveness of switching paroxetine formulation for treatment of major depressive disorder: an open-label multicenter study

“… 9 , 11 Moreover, patient satisfaction at week 8 was good, which was also consistent with that of a post-marketing surveillance study of CR paroxetine (68.7% vs 69.8%). 11 As suggested by Kato et al, 11 the reason for the low incidence of ADRs is the prolonged exposure to paroxetine (IR treatment for ≥6 months) before switching to CR formulation. This is because several adverse reactions that cause the premature discontinuation of SSRIs tend to occur during the early stages of treatment.…”

“…The incidence of ADRs was 12.4% in this study, which is comparable to the results of a recent report regarding the safety and effectiveness of CR paroxetine in 3,213 Japanese patients with depression who switched from antidepressants of other classes (11.2%). 11 Further, the incidence of ADRs during IR paroxetine use has been reported as 22.4% (1,453 in 6,482 subjects) in similar post-marketing surveillance of patients with depression, panic disorder, obsessive–compulsive disorder, and social anxiety disorder in Japan; 35 however, the survey for CR paroxetine only included depressive patients. The reported incidence of somnolence and nausea was also consistent with that reported in previous studies.…”

“…Patient preference for CR paroxetine over the prior antidepressant was rated as follows: much better, moderately better, slightly better, similar, slightly worse, moderately worse, and much worse. 11 Finally, the safety of CR paroxetine was evaluated based on the reported adverse drug reactions (ADRs) and common laboratory test results during the study period.…”